Athletic gear or other devices comprising post-molded expandable components

ABSTRACT

A device (e.g., an article of athletic gear) comprising a post-molded expandable component, which is a part of the device that is configured to be expanded or has been expanded after being molded. This may allow the post-molded expandable component to have enhanced characteristics (e.g., be more shock-absorbent, lighter, etc.), to be cost-effectively manufactured (e.g., by using less material and/or making it in various sizes), and/or to be customized for a user (e.g., by custom-fitting it to the user).

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from U.S. Provisional PatentApplication 62/292,947 filed on Feb. 9, 2016 and incorporated byreference herein.

FIELD

The invention generally relates to devices (e.g., athletic gear,personal protective equipment, clothing, etc.) comprising molded partsand to materials from which these molded parts are made.

BACKGROUND

Manufacturing of various devices often involves molding parts of thesedevices, such as by injection molding, compression molding,thermoforming, etc. For example, athletic gear such as helmets, shoulderpads, sporting implements (e.g., hockey sticks), etc., typicallycomprise molded parts.

Molding of parts usually entails providing materials (e.g., as liquids,solids, semi-solids, or paste) in molds in which these materials areformed to substantially final dimensions of the parts. In some cases,this may present certain drawbacks. For example, molding parts ofdifferent sizes normally requires molds of different sizes. As anotherexample, characteristics of molded parts are often dictated or affectedby their molding process.

For these and other reasons, there is a need to improve devicescomprising molded parts.

SUMMARY

According to various aspects of the invention, there is provided adevice (e.g., an article of athletic gear) comprising a post-moldedexpandable component, which is a part of the device that is configuredto be expanded or has been expanded after being molded.

This may allow the post-molded expandable component to have enhancedcharacteristics (e.g., be more shock-absorbent, lighter, etc.), to becost-effectively manufactured (e.g., by using less material and/ormaking it in various sizes), and/or to be customized for a user (e.g.,by custom-fitting it to the user).

For example, according to an aspect of the invention, there is provideda component comprising an expandable material molded into an initialshape and expandable to an expanded shape that is a scaled-up version ofthe initial shape in response to a stimulus after molding.

According to another aspect of the invention, there is provided acomponent comprising a material molded into a shape. The materialcomprises a polymeric substance and expandable microspheres. Theexpandable microspheres constitute at least 10% of the material byweight. A resilience of the material is less than a resilience of theexpandable microspheres according to ASTM D2632-01.

According to another aspect of the invention, there is provided acomponent comprising a material molded into a shape. The materialcomprises a polymeric substance and expandable microspheres. Theexpandable microspheres constitute at least 10% of the material byweight. A resilience of the material is no more than 40% according toASTM D2632-01.

According to another aspect of the invention, there is provided acomponent comprising a material molded into a shape. The materialcomprises a polymeric substance and expandable microspheres. Theexpandable microspheres constitute at least 10% of the material byweight. A tensile strength of the material is greater than a tensilestrength of the expandable microspheres.

According to another aspect of the invention, there is provided acomponent comprising a material molded into a shape. The materialcomprises a polymeric substance and expandable microspheres. Theexpandable microspheres constitute at least 10% of the material byweight. A tensile strength of the material is at least 0.9 MPa.

According to another aspect of the invention, there is provided acomponent comprising a material molded into a shape. The materialcomprises a polymeric substance and expandable microspheres. Theexpandable microspheres constitute at least 10% of the material byweight. An elongation at break of the material is greater than anelongation at break of the expandable microspheres.

According to another aspect of the invention, there is provided acomponent comprising a material molded into a shape. The materialcomprises a polymeric substance and expandable microspheres. Theexpandable microspheres constitute at least 10% of the material byweight. An elongation at break of the material is at least 20%.

According to another aspect of the invention, there is provided acomponent comprising an expandable material molded into an initial shapeand expandable to an expanded shape that is a scaled-up version of theinitial shape in response to a stimulus after molding. The expandablematerial comprises a polymeric substance and an expansion agent. Atemperature of the expandable material during molding is lower than anexpansion temperature of the expansion agent.

According to another aspect of the invention, there is provided acomponent comprising an expandable material molded into an initial shapeand expandable to an expanded shape that is a scaled-up version of theinitial shape in response to a stimulus initiated a substantial amountof time after molding.

According to another aspect of the invention, there is provided acomponent comprising an expandable material molded into an initial shapein a mold and expandable to an expanded shape that is a scaled-upversion of the initial shape in response to a stimulus upon removal fromthe mold.

According to another aspect of the invention, there is provided a methodof making a component. The method comprises: causing molding of anexpandable material into an initial shape; and causing expansion of theexpandable material to an expanded shape that is a scaled-up version ofthe initial shape in response to a stimulus after the molding of theexpandable material.

According to another aspect of the invention, there is provided a devicecomprising a component as discussed above. In various examples, thedevice may be an article of athletic gear for a user, such as an articleof protective athletic gear wearable by the user to protect the user ora sports implement for handling by the user.

These and other aspects of the invention will now become apparent tothose of ordinary skill in the art upon review of the followingdescription of embodiments of the invention in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of embodiments of the invention is providedbelow, by way of example only, with reference to the accompanyingdrawings, in which:

FIG. 1 shows an example of a device comprising a plurality ofpost-molded expandable components in accordance with an embodiment ofthe invention, in which the device is a helmet for protecting a user'shead;

FIGS. 2 shows a front view of the helmet;

FIGS. 3 and 4 show rear perspective views of the helmet;

FIGS. 5 to 8 show operation of an example of an adjustment mechanism ofthe helmet;

FIG. 9 shows internal dimensions of a head-receiving cavity of thehelmet;

FIGS. 10 and 11 show an example of shell members of an outer shell ofthe helmet;

FIGS. 12 to 16 show an example of a plurality of post-molded expandablecomponents constituting a plurality of pads of an inner liner of thehelmet;

FIG. 17 shows an example of a precursor of a post-molded expandablecomponent being expanded to form the post-molded expandable component;

FIG. 18 is a block diagram representing an example of an expandablematerial of the post-molded expandable component;

FIG. 19 shows an example of an expansion agent of the expandablematerial of the post-molded expandable component;

FIG. 20 shows an example of a molding apparatus for molding theprecursor of the post-molded expandable component;

FIG. 21 shows an example of a 3D printer for printing a mold used formolding the precursor of the post-molded expandable component;

FIG. 22 is a flow diagram showing the mold being used to produce theprecursor which can be expanded into different sizes of the post-moldedexpandable component;

FIG. 23 shows an oven that subjects the expandable material to heat inorder to expand the precursor to form the post-molded expandablecomponent;

FIG. 24 shows an example of a variant in which the precursor is cast;

FIGS. 25A and 25B show examples of an extrusion mechanism for formingthe expandable material into a thermoformable sheet in accordance withanother variant;

FIGS. 26 and 27 show an example of a thermoforming process for moldingthe thermoformable sheet to form the precursor;

FIG. 28 shows an embodiment according to which the post-moldedexpandable component is comprised by a chin cup of the helmet;

FIG. 29 show an embodiment in which the post-molded expandable componentis comprised by an arm guard;

FIG. 30 shows an embodiment in which the post-molded expandablecomponent is comprised by shoulder pads;

FIG. 31 shows an embodiment in which the post-molded expandablecomponent is comprised by a leg guard;

FIG. 32 shows an embodiment in which the post-molded expandablecomponent is comprised by a chest protector;

FIG. 33 shows an embodiment in which the post-molded expandablecomponent is comprised by a blocker glove;

FIG. 34 shows an embodiment in which the post-molded expandablecomponent is comprised by a hockey goalkeeper leg pad;

FIG. 35 shows an embodiment in which a skate comprises the post-moldedexpandable component;

FIGS. 36A shows an example of an embodiment in which the post-moldedexpandable component is comprised by a hockey stick;

FIG. 36B shows a cross-section of a blade of the hockey stick of FIG.36A;

FIG. 37 shows another example of an embodiment in which the post-moldedexpandable component is comprised by a hockey stick;

FIG. 38 shows an embodiment in which the post-molded expandablecomponent is comprised by a lacrosse stick;

FIG. 39 shows an example of a configuration of the mold used to form theprecursor;

FIG. 40 shows an example of the mold when it is thermoformed;

FIG. 41 shows a top view of the mold of FIG. 40 when two halves of themold are assembled;

FIGS. 42A and 42B show an example of a compression device used forforming the precursor with the mold of FIGS. 40 and 41;

FIG. 43 shows an example of a variant in which the post-moldedexpandable component comprises a plurality of expandable materials;

FIG. 44 shows an example of a variant in which the expandable materialof the post-molded expandable component is subjected to infrared lightto cause the expandable material to expand;

FIG. 45 shows an example of a variant in which a pad comprising thepost-molded expandable component comprises a decorative outer layerconstituting at least part of an outer surface of the pad;

FIG. 46A shows an embodiment in which the post-molded expandablecomponent is comprised by a ball bat;

FIG. 46B shows a cross-section of the ball bat of FIG. 46A; and

FIGS. 47 and 48 show the head of the user.

It is to be expressly understood that the description and drawings areonly for the purpose of illustrating certain embodiments of theinvention and are an aid for understanding. They are not intended to bea definition of the limits of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

FIG. 1 shows an example of a device 10 comprising a plurality ofpost-molded expandable components 12 ₁-12 _(E) in accordance with anembodiment of the invention. In this embodiment, the device 10 is anarticle of athletic gear for a user engaging in a sport or otherathletic activity. More particularly, in this embodiment, the article ofathletic gear 10 is an article of protective athletic gear wearable bythe user to protect him/her. Specifically, in this example, the articleof protective athletic gear 10 is a helmet for protecting a head of theuser against impacts. In this case, the helmet 10 is a hockey helmet forprotecting the head of the user, who is a hockey player, against impacts(e.g., from a puck or ball, a hockey stick, a board, ice or anotherplaying surface, etc., with another player, etc.).

Each of the post-molded expandable components 12 ₁-12 _(E) of the helmet10 is a part of the helmet 10 that is configured to be expanded or hasbeen expanded after being molded (i.e., shaped in a mold). This mayallow each of the post-molded expandable components 12 ₁-12 _(E) of thehelmet 10 to have enhanced characteristics (e.g., be moreshock-absorbent, lighter, etc.), to be cost-effectively manufactured(e.g., by using less material and/or making it in various sizes), and/orto be customized for the user (e.g., by custom-fitting it to the userin-store or at another location where it can be expanded to conform tothe user).

In this embodiment, the helmet 10 comprises an outer shell 11 and aninner liner 15 that includes the post-molded expandable components 12₁-12 _(E) of the helmet 10. The helmet 10 also comprises a chinstrap 16for securing the helmet 10 to the player's head. The helmet 10 may alsocomprise a faceguard (not shown) to protect at least part of theplayer's face (e.g., a grid (sometimes referred to as a “cage”) or avisor (sometimes referred to as a “shield”)).

The helmet 10 defines a cavity 13 for receiving the player's head. Inresponse to an impact, the helmet 10 absorbs energy from the impact toprotect the player's head. The helmet 10 protects various regions of theplayer's head. As shown in FIGS. 47 and 48, the player's head comprisesa front region FR, a top region TR, left and right side regions LS, RS,a back region BR, and an occipital region OR. The front region FRincludes a forehead and a front top part of the player's head andgenerally corresponds to a frontal bone region of the player's head. Theleft and right side regions LS, RS are approximately located above theplayer's ears. The back region BR is opposite the front region FR andincludes a rear upper part of the player's head. The occipital region ORsubstantially corresponds to a region around and under the head'soccipital protuberance.

The helmet 10 comprises an external surface 18 and an internal surface20 that contacts the player's head when the helmet 10 is worn. Thehelmet 10 has a front-back axis FBA, a left-right axis LRA, and avertical axis VA which are respectively generally parallel to adorsoventral axis, a dextrosinistral axis, and a cephalocaudal axis ofthe player when the helmet 10 is worn and which respectively define afront-back direction, a lateral direction, and a vertical direction ofthe helmet 10. Since they are generally oriented longitudinally andtransversally of the helmet 10, the front-back axis FBA and theleft-right axis LRA can also be referred to as a longitudinal axis and atransversal axis, respectively, while the front-back direction and thelateral direction can also be referred to a longitudinal direction and atransversal direction, respectfully.

The outer shell 11 provides strength and rigidity to the helmet 10. Tothat end, the outer shell 11 comprises a rigid material 27. For example,in various embodiments, the rigid material 27 of the outer shell 11 maybe a thermoplastic material such as polyethylene (PE), polyamide(nylon), or polycarbonate, a thermosetting resin, or any other suitablematerial. The outer shell 11 includes an inner surface 17 facing theinner liner 15 and an outer surface 19 opposite the inner surface 17.The outer surface 19 of the outer shell 11 constitutes at least part ofthe external surface 18 of the helmet 10.

In this embodiment, the outer shell 11 comprises a front shell member 22and a rear shell member 24 that are connected to one another. The frontshell member 22 comprises a top portion 21 for facing at least part ofthe top region TR of the player's head, a front portion 23 for facing atleast part of the front region FR of the player's head, and left andright lateral side portions 25L, 25R extending rearwardly from the frontportion 23 for facing at least part of the left and right side regionsLS, RS of the player's head, respectively. The rear shell member 24comprises a top portion 29 for facing at least part of the top region TRof the player's head, a back portion 31 for facing at least part of theback region BR of the player's head, an occipital portion 33 for facingat least part of the occipital region OR of the player's head, and leftand right lateral side portions 35L, 35R extending forwardly from theback portion 31 for facing at least part of the left and right sideregions LS, RS of the player's head, respectively.

In this embodiment, the helmet 10 is adjustable to adjust how it fits onthe player's head. To that end, the helmet 10 comprises an adjustmentmechanism 40 for adjusting a fit of the helmet 10 on the player's head.The adjustment mechanism 40 may allow the fit of the helmet 10 to beadjusted by adjusting one or more internal dimensions of the cavity 13of the helmet 10, such as a front-back internal dimension FBD of thecavity 13 in the front-back direction of the helmet 10 and/or aleft-right internal dimension LRD of the cavity 13 in the left-rightdirection of the helmet 10, as shown in FIG. 9.

More particularly, in this embodiment, the adjustment mechanism 40 isconfigured such that the outer shell 11 and the inner liner 15 areadjustable to adjust the fit of the helmet 10 on the player's head. Tothat end, in this embodiment, the front shell member 22 and the rearshell member 24 are movable relative to one another to adjust the fit ofthe helmet 10 on the player's head. In this example, relative movementof the outer shell members 22, 24 for adjustment purposes is in thefront-back direction of the helmet 10 such that the front-back internaldimension FBD of the cavity 13 of the helmet 10 is adjusted. This isshown in FIGS. 5 to 8 in which the rear shell member 24 is movedrelative to the front shell member 22 from a first position, which isshown in FIG. 5 and which corresponds to a minimum size of the helmet10, to a second position, which is shown in FIG. 6 and which correspondsto an intermediate size of the helmet 10, and to a third position, whichis shown in FIGS. 7 and 8 and which corresponds to a maximum size of thehelmet 10.

In this example of implementation, the adjustment mechanism 40 comprisesan actuator 41 that can be moved (in this case pivoted) by the playerbetween a locked position, in which the actuator 41 engages a lockingpart 45 (as best shown in FIGS. 10 and 11) of the front shell member 22and thereby locks the outer shell members 22, 24 relative to oneanother, and a release position, in which the actuator 41 is disengagedfrom the locking part 45 of the front shell member 22 and therebypermits the outer shell members 22, 24 to move relative to one anotherso as to adjust the size of the helmet 10. The adjustment mechanism 40may be implemented in any other suitably way in other embodiments.

The inner liner 15 is disposed between the outer shell 11 and theplayer's head to absorb impact energy when the helmet 10 is impacted.More particularly, the inner liner 15 comprises a shock-absorbingstructure 32 that includes an outer surface 38 facing towards the outershell 11 and an inner surface 34 facing towards the player's head. Forexample, in some embodiments, the shock-absorbing structure 32 of theinner liner 15 may comprise a shock-absorbing material. For instance, insome cases, the shock-absorbing material may include a polymericcellular material, such as a polymeric foam (e.g., expandedpolypropylene (EPP) foam, expanded polyethylene (EPE) foam, or any othersuitable polymeric foam material), or expanded polymeric microspheres(e.g., Expancel™ microspheres commercialized by Akzo Nobel). Any othermaterial with suitable impact energy absorption may be used in otherembodiments. Additionally or alternatively, in some embodiments, theshock-absorbing structure 32 of the inner liner 15 may comprise an arrayof shock absorbers that are configured to deform when the helmet 10 isimpacted. For instance, in some cases, the array of shock absorbers mayinclude an array of compressible cells that can compress when the helmet10 is impacted. Examples of this are described in U.S. Pat. No.7,677,538 and U.S. Patent Application Publication 2010/0258988, whichare incorporated by reference herein. The inner liner 15 may be mountedto the outer shell 11 in any suitable way. For example, in someembodiments, the inner liner 15 may be mounted to the outer shell 11 byone or more fasteners such as mechanical fasteners (e.g., tacks,staples, rivets, screws, stitches, etc.), an adhesive, or any othersuitable fastener.

In this embodiment, the inner liner 15 comprises a plurality of pads 36₁-36 _(A), 37 ₁-37 _(C) disposed between the outer shell 11 and theplayer's head when the helmet 10 is worn. In this example, respectiveones of the pads 36 ₁-36 _(A), 37 ₁-37 _(C) are movable relative to oneanother and with the outer shell members 22, 24 to allow adjustment ofthe fit of the helmet 10 using the adjustment mechanism 40.

The pads 36 ₁-36 _(A) are responsible for absorbing at least a bulk ofthe impact energy transmitted to the inner liner 15 when the helmet 10is impacted and can therefore be referred to as “absorption” pads. Inthis embodiment, the pad 36 ₁ is for facing at least part of the frontregion FR and left side region LS of the player's head, the pad 36 ₂ isfor facing at least part of the front region FR and right side region RSof the player's head, the pad 36 ₃ is for facing at least part of theback region BR and left side region LS of the player's head, the pad 36₄ is for facing at least part of the back region BR and right sideregion RS of the player's head, and the pad 365 is for facing at leastpart of the top region TR and back region BR of the player's head. Thefront shell member 22 overlays the pads 36 ₁, 36 ₂ while the rear shellmember 24 overlays the pads 36 ₃, 36 ₄.

The pads 37 ₁-37 _(C) are responsible to provide comfort to the player'shead and can therefore be referred to as “comfort” pads. The comfortpads 37 ₁-37 _(C) may comprise any suitable soft material providingcomfort to the player. For example, in some embodiments, the comfortpads 37 ₁-37 _(C) may comprise polymeric foam such as polyvinyl chloride(PVC) foam, polyurethane foam (e.g., PORON XRD foam commercialized byRogers Corporation), vinyl nitrile foam or any other suitable polymericfoam material. In some embodiments, given ones of the comfort pads 37₁-37 _(C) may be secured (e.g., adhered, fastened, etc.) to respectiveones of the absorption pads 36 ₁-36 _(A). In other embodiments, givenones of the comfort pads 36 ₁-36 _(A) may be mounted such that they aremovable relative to the absorption pads 37 ₁-37 _(C). For example, insome embodiments, one or more of the comfort pads 37 ₁-37 _(C) may bepart of a floating liner as described in U.S. Patent ApplicationPublication 2013/0025032, which, for instance, may be implemented as theSUSPEND-TECH™ liner member found in the BAUER™ RE-AKT™ and RE-AKT 100™helmets made available by Bauer Hockey, Inc.. The comfort pads 37 ₁-37_(C) may assist in absorption of energy from impacts, in particular,low-energy impacts.

The inner liner 15 comprises the post-molded expandable components 12₁-12 _(E) of the helmet 10. More particularly, in this embodiment,respective ones of the pads 36 ₁-36 _(A) comprise respective ones of thepost-molded expandable components 12 ₁-12 _(E) of the helmet 10.Specifically, in this example, each post-molded expandable component 12_(x) of the helmet 10 constitutes a pad 36 _(x).

With additional reference to FIGS. 17 and 18, the post-molded expandablecomponent 12 _(x) of the helmet 10 constituting the pad 36 _(x)comprises an expandable material 50 that is molded into a precursor 12_(x)* which can then be expanded by a stimulus (e.g., heat or anotherstimulus) to an expanded shape that is a scaled-up version of an initialshape of the precursor 12 _(x)*. Thus, in this example, athree-dimensional configuration of the initial shape of the precursor 12_(x)* is such that, once the expandable material 50 is expanded, athree-dimensional configuration of the expanded shape of the post-moldedexpandable component 12 _(x) imparts a three-dimensional configurationof the pad 36 _(x) (e.g., including curved and/or angular parts of thepad 36 _(x)).

The post-molded expandable component 12 _(x) of the helmet 10constituting the pad 36 _(x) is “expandable” in that it is capable ofexpanding and/or has been expanded by a substantial degree in responseto a stimulus after being molded. That is, an expansion ratio of thepost-molded expandable component 12 _(x) of the helmet 10 constitutingthe pad 36 _(x), which refers to a ratio of a volume of the post-moldedexpandable component 12 _(x) of the helmet 10 after the expandablematerial 50 has been expanded subsequently to having been molded intothe precursor 12 _(x)* over a volume of the precursor 12 _(x)* intowhich the expandable material 50 is initially molded, may besignificantly high. For example, in some embodiments, the expansionratio of the post-molded expandable component 12 _(x) of the helmet 10constituting the pad 36 _(x) may be at least 2, in some cases at least3, in some cases at least 5, in some cases at least 10, in some cases atleast 20, in some cases at least 30, in some cases at least 40 and insome cases even more (e.g., 45).

The expandable material 50 can be any material capable of expandingafter being molded. In this embodiment, the expandable material 50includes a mixture of a polymeric substance 52 and an expansion agent 54that allows the expandable material 50 to expand. Once expanded into itsfinal shape, the pad 36 _(x) may have desirable properties, such asbeing more shock-absorbent than it if had been made entirely of theexpansion agent 54 and/or being lighter than if it had been madeentirely of the polymeric substance 52.

The polymeric substance 52 constitutes a substantial part of theexpandable material 50 and substantially contributes to structuralintegrity to the pad 36 _(x). For instance, in some embodiments, thepolymeric substance 52 may constitute at least 40%, in some cases atleast 50%, in some cases at least 60%, in some cases at least 70%, insome cases at least 80%, and in some cases at least 90% of theexpandable material 50 by weight.

In this example of implementation, the polymeric substance 52 mayconstitute between 50% and 90% of the expandable material 50 by weight.

In this embodiment, the polymeric substance 52 may be an elastomericsubstance. For instance, the polymeric substance 52 may be athermoplastic elastomer (TPE) or a thermoset elastomer (TSE).

More particularly, in this embodiment, the polymeric substance 52comprises polyurethane. The polyurethane 52 may be composed of anysuitable constituents such as isocyanates and polyols and possiblyadditives. For instance, in some embodiments, the polyurethane 52 mayhave a hardness in a scale of Shore 00, Shore A, Shore C or Shore D, orequivalent. For example, in some embodiments, the hardness of thepolyurethane 52 may be between Shore 5A and 95A or between Shore D 40Dto 93D. Any other suitable polyurethane may be used in otherembodiments. The polymeric substance 52 may comprise any other suitablepolymer in other embodiments. For example, in some embodiments, thepolymeric substance 52 may comprise silicon, rubber, etc.

The expansion agent 54 is combined with the polyurethane 52 to enableexpansion of the expandable material 50 to its final shape after it hasbeen molded. A quantity of the expansion agent 54 allows the expandablematerial 50 to expand by a substantial degree after being molded. Forinstance, in some embodiments, the expansion agent 54 may constitute atleast 10%, in some cases at least 20%, in some cases at least 30%, insome cases at least 40%, in some cases at least 50%, and in some casesat least 60%, of the expandable material 50 by weight and in some caseseven more. In this example of implementation, the expansion agent 54 mayconstitute between 15% and 50% of the expandable material 50 by weight.Controlling the quantity of the expansion agent 54 may allow control ofthe expansion ratio of the post-molded expandable component 12 _(x).

In this embodiment, as shown in FIG. 19, the expansion agent 54comprises an amount of expandable microspheres 60 ₁-60 _(M). Eachexpandable microsphere 60 _(i) comprises a polymeric shell 62 expandableby a fluid encapsulated in an interior of the polymeric shell 62. Inthis example of implementation, the polymeric shell 62 of the expandablemicrosphere 60 _(i) is a thermoplastic shell. The fluid encapsulated inthe polymeric shell 62 is a liquid or gas (in this case a gas) able toexpand the expandable microsphere 60 _(i) when heated duringmanufacturing of the pad 36 _(x). In some embodiments, the expandablemicrospheres 60 ₁-60 _(M) may be Expancel™ microspheres commercializedby Akzo Nobel. In other embodiments, the expandable microspheres 60 ₁-60_(M) may be Dualite microspheres commercialized by Henkel; Advancellmicrospheres commercialized by Sekisui; Matsumoto Microspheremicrospheres commercialized by Matsumoto Yushi Seiyaku Co; or KUREHAMicrosphere microspheres commercialized by Kureha. Various other typesof expandable microspheres may be used in other embodiments.

In this example of implementation, the expandable microspheres 60 ₁-60_(M) include dry unexpanded (DU) microspheres when combined with thepolymeric substance 52 to create the expandable material 50 before theexpandable material 50 is molded and subsequently expanded. Forinstance, the dry unexpanded (DU) microspheres may be provided as apowder mixed with one or more liquid constituents of the polymericsubstance 52.

The expandable microspheres 60 ₁-60 _(M) may be provided in variousother forms in other embodiments. For example, in some embodiments, theexpandable microspheres 60 ₁-60 _(M) may include dry expanded, wetand/or partially-expanded microspheres. For instance, wet unexpandedmicrospheres may be used to get better bonding with the polymericsubstance 52. Partially-expanded microspheres may be used to employ lessof the polymeric substance 52, mix with the polymeric substance 52 insemi-solid form, or reduce energy to be subsequently provided forexpansion.

In some embodiments, the expandable microspheres 60 ₁-60 _(M) mayconstitute at least 10%, in some cases at least 20%, in some cases atleast 30%, in some cases at least 40%, in some cases at least 50%, andin some cases at least 60% of the expandable material 50 by weight andin some cases even more. In this example of implementation, theexpandable microspheres 601-60 _(M) may constitute between 15% and 50%of the expandable material 50 by weight.

The post-molded expandable component 12 _(x) of the helmet 10constituting the pad 36 _(x) may have various desirable qualities.

For instance, in some embodiments, the pad 36 _(x) may be less dense andthus lighter than if it was entirely made of the polyurethane 52, yet bemore shock-absorbent and/or have other better mechanical properties thanif it was entirely made of the expandable microspheres 60 ₁-60 _(M).

For example, in some embodiments, a density of the expandable material50 of the pad 36 _(x) may be less than a density of the polyurethane 52(alone). For instance, the density of the expandable material 50 of thepad 36 _(x) may be no more than 70%, in some cases no more than 60%, insome cases no more than 50%, in some cases no more than 40%, in somecases no more than 30%, in some cases no more than 20%, in some cases nomore than 10%, and in some cases no more than 5% of the density of thepolyurethane 52 and in some cases even less. For example, in someembodiments, the density of the expandable material 50 of the pad 36_(x) may be between 2 to 75 times less than the density of thepolyurethane 52 ,i.e., the density of the expandable material 50 of thepad 36 _(x) may be about 1% to 50% of the density of the polyurethane52).

The density of the expandable material 50 of the pad 36 _(x) may haveany suitable value. For instance, in some embodiments, the density ofthe expandable material 50 of the pad 36 _(x) may be no more than 0.7g/cm³, in some cases no more than 0.4 g/cm³ , in some cases no more than0.1 g/cm³, in some cases no more than 0.080 g/cm³, in some cases no morethan 0.050 g/cm³, in some cases no more than 0.030 g/cm³, and/or may beat least 0.010 g/cm³. In some examples of implementation, the density ofthe expandable material 50 may be between 0.015 g/cm³ and 0.080 g/cm³,in some cases between 0.030 g/cm³ and 0.070 g/cm³, and in some casesbetween 0.040 g/cm³ and 0.060 g/cm³.

As another example, in some embodiments, a stiffness of the expandablematerial 50 of the pad 36 _(x) may be different from (i.e., greater orless than) a stiffness of the expandable microspheres 60 ₁-60 _(M)(alone). For instance, a modulus of elasticity (i.e., Young's modulus)of the expandable material 50 of the pad 36 _(x) may be greater or lessthan a modulus of elasticity of the expandable microspheres 60 ₁-60 _(M)(alone). For instance, a difference between the modulus of elasticity ofthe expandable material 50 of the pad 36 _(x) and the modulus ofelasticity of the expandable microspheres 60 ₁-60 _(M) may be at least20%, in some cases at least 30%, in some cases at least 50%, and in somecases even more, measured based on a smaller one of the modulus ofelasticity of the expandable material 50 of the pad 36 _(x) and themodulus of elasticity of the expandable microspheres 60 ₁-60 _(M). Insome cases, the modulus of elasticity may be evaluated according to ASTMD-638 or ASTM D-412.

As another example, in some embodiments, a resilience of the expandablematerial 50 of the pad 36 _(x) may be less than a resilience of theexpandable microspheres 60 ₁-60 _(M) (alone). For instance, in someembodiments, the resilience of the expandable material 50 of the pad 36_(x) may be no more than 70%, in some cases no more than 60%, in somecases no more than 50%, in some cases no more than 40%, in some cases nomore than 30%, in some cases no more than 20%, and in some cases no morethan 10% of the resilience of the expandable microspheres 60 ₁-60 _(M)according to ASTM D2632-01 which measures resilience by verticalrebound. In some examples of implementation, the resilience of theexpandable material 50 of the pad 36 _(x) may be between 20% and 60% ofthe resilience of the expandable microspheres 60 ₁-60 _(M).Alternatively, in other embodiments, the resilience of the expandablematerial 50 of the pad 36 _(x) may be greater than the resilience of theexpandable microspheres 60 ₁-60 _(M).

The resilience of the expandable material 50 of the pad 36 _(x) may haveany suitable value. For instance, in some embodiments, the resilience ofthe expandable material 50 of the pad 36 _(x) may be no more than 40%,in some cases no more than 30%, in some cases no more than 20%, in somecases no more than 10% and in some cases even less (e.g., 5%), accordingto ASTM D2632-01, thereby making the pad 36 _(x) more shock-absorbent.In other embodiments, the resilience of the expandable material 50 ofthe pad 36 _(x) may be at least 60%, in some cases at least 70%, in somecases at least 80% and in some cases even more, according to ASTMD2632-01, thereby making the expandable material 50 provide more rebound(e.g., which may be useful in other embodiments where the post-moldedexpandable component 12 _(x) is part of other devices, as discussedlater).

As another example, in some embodiments, a tensile strength of theexpandable material 50 of the pad 36 _(x) may be greater than a tensilestrength of the expandable microspheres 60 ₁-60 _(M) (alone). Forinstance, in some embodiments, the tensile strength of the expandablematerial 50 of the pad 36 _(x) may be at least 120%, in some cases atleast 150%, in some cases at least 200%, in some cases at least 300%, insome cases at least 400%, and in some cases at least 500% of the tensilestrength of the expandable microspheres 60 ₁-60 _(M) according to ASTMD-638 or ASTM D-412, and in some cases even more.

The tensile strength of the expandable material 50 of the pad 36 _(x)may have any suitable value. For instance, in some embodiments, thetensile strength of the expandable material 50 of the pad 36 _(x) may beat least 0.9 MPa, in some cases at least 1 MPa, in some cases at least1.2 MPa, in some cases at least 1.5 MPa and in some cases even more(e.g. 2 MPa or more).

As another example, in some embodiments, an elongation at break of theexpandable material 50 of the pad 36 _(x) may be greater than anelongation at break of the expandable microspheres 60 ₁-60 _(M) (alone).For instance, in some embodiments, the elongation at break of theexpandable material 50 of the pad 36 _(x) may be at least 120%, in somecases at least 150%, in some cases at least 200%, in some cases at least300%, in some cases at least 400%, and in some cases at least 500% ofthe elongation at break of the expandable microspheres 60 ₁-60 _(M)according to ASTM D-638 or ASTM D-412, and in some cases even more.

The elongation at break of the expandable material 50 of the pad 36 _(x)may have any suitable value. For instance, in some embodiments, theelongation at break of the expandable material 50 of the pad 36 _(x) maybe at least 20%, in some cases at least 30%, in some cases at least 50%,in some cases at least 75%, in some cases at least 100%, and in somecases even more (e.g. 150% or more).

With additional reference to FIG. 20, in this embodiment, thepost-molded expandable component 12 _(x) constituting the pad 36 _(x) ofthe helmet 10 may be manufactured by: providing the expandable material50; molding the expandable material 50 into the precursor 12 _(x)* in amold 70; and expanding the expandable material 50 to the expanded shapewhich is the scaled-up version of the initial shape of the precursor 12_(x)* and which corresponds to the three-dimensional configuration ofthe post-molded expandable component 12 _(x), by subjecting theprecursor 12 _(x)* made of the expanded material 50 to a stimulus (e.g.,heat) after the precursor 12 _(x)* has been molded (e.g., outside of themold 70). That is, expansion of the precursor 12 _(x)* made of theexpanded material 50 to the expanded shape of the post-molded expandablecomponent 12 _(x) is caused by energy transmitted to the precursor 12_(x)* made of the expanded material 50 after the precursor 12 _(x)* hasbeen molded (e.g., outside of the mold 70).

The expandable material 50 may be provided in any suitable way and anysuitable molding process using the mold 70 may be used to mold theexpandable material 50 into the precursor 12 _(x)*.

In this embodiment, the expandable material 50 is provided as a fluidflowing into the mold 70 to undergo the molding process to mold theexpandable material 50 into the precursor 12 _(x)*. In particular, inorder to obtain the expandable material 50, the expandable microspheres60 ₁-60 _(M) are combined with the polyurethane 52. For instance, theexpandable microspheres 60 ₁-60 _(M) may be introduced into one or morecomponents of the polyurethane 52 prior to mixing of the components ofthe polyurethane 52 (e.g., isocyanates and/or polyols). For example, inthis embodiment, the expandable microspheres 60 ₁-60 _(M) are introducedinto the isocyanates of the polyurethane 52 prior to mixing theisocyanates, the polyols and any other components of the polyurethane 52if any. This may allow the isocyanates to react to the moisture presentin the expandable microspheres 60 ₁-60 _(M). The expandable microspheres60 ₁-60 _(M) may be introduced into the polyols of the polyurethane 52in other embodiments. Moreover, in this example, the expandablemicrospheres 60 ₁-60 _(M) are introduced into the polyurethane 52 as dryunexpanded microspheres.

Also, in this embodiment, the molding process of the precursor 12 _(x)*is a low-temperature molding process during which a temperature of theexpandable material 50 being molded is lower than an expansiontemperature at which the expandable microspheres 60 ₁-60 _(M) areexpanded. For instance, in some embodiments where the expansiontemperature of the expandable microspheres 60 ₁-60 _(M) may be 70° C. ormore, the molding process may be carried out such that the temperatureof the expandable material 50 being molded is less than 70° C. (e.g.,40° C.).

In this example, the molding process of the precursor 12 _(x)* is alsodone at low pressure such that it is a low-temperature and low-pressuremolding process. This may be done since expansion of the expandablematerial 50 occurs after it has been molded (e.g., outside of the mold70).

More particularly, in this embodiment, the molding process of theprecursor 12 _(x)* is injection molding. For instance, in thisembodiment, the molding process is carried out via a molding apparatus75 comprising the mold 70. In this example, the molding process includesfeeding the expandable material 50 into a barrel of the moldingapparatus 75 (e.g., via a hopper) in which a mechanism (e.g., a screwmechanism) causes displacement of the expandable material 50 towards asprue of the mold 70. Once the expandable material 50 reaches the sprueof the mold 70, the expandable material 50 is injected into a moldcavity 72 of the mold 70 that is shaped like the precursor 12 _(x)*.After the expandable material 50 has shaped into it, the precursor 12_(x)* is removed from the mold 70. One or more finishing operations maybe carried out in order to produce the finished precursor 12 _(x)*(e.g., deflashing).

In some cases, the molding process of the precursor 12 _(x)* may use oneor more inserts (e.g., cores) which are disposed within the mold 70prior to forming the precursor 12 _(x)* and which are configured to formempty spaces within the precursor 12 _(x)* (e.g., vents). Such insertsmay comprise a material having a low melting temperature. For example,the material of the inserts may comprise wax, expanded polyethylene(EPE), expanded polystyrene (EPS), or any other suitable material.

Since in this embodiment the molding process is a low-temperature andlow-pressure injection molding process, production of the mold 70 may beless expensive and safer than if a high-temperature and/or high-pressureinjection molding process was implemented. Moreover, this may result inan overall lowered stress condition in the precursor 12 _(x)*.

The mold 70 in which the expandable material 50 is molded may beprovided in any suitable way in various embodiments.

For example, in this embodiment, the mold 70 may be created by additivemanufacturing, a.k.a., 3D printing, such as selective laser sintering(SLS), stereolithography (SLA), etc. This may be facilitated since themold 70 may be relatively small, given that the expandable material 50will be expanded after being molded in the mold 70.

More particularly, in this embodiment, as shown in FIG. 21, the mold 70is made by a 3D printer 76. The 3D printer 76 is configured to form athree-dimensional object based at least in part on a design file (e.g.,a CAD file) that is generated on a computing apparatus (e.g., a desktopcomputer, a laptop, a tablet, a smartphone, etc.). To that end, the 3Dprinter 76 deposits layers of material on top of one another in order toform the three-dimensional object. For instance, the 3D printer 76 maygenerally include a printer head (e.g., an extruder) that is movablealong two or more axes (e.g., an x-axis and a z-axis) and a printer bedthat may be stationary or movable along one or more axes (e.g., ay-axis). The 3D printer 76 may be configured in various other ways inother embodiments (e.g., having components movable along a polarcoordinate system).

Thus, in this embodiment, the mold 70 comprises a printed material 74that is layered by the 3D printer 76 in order to form the mold 70. Inthis embodiment, the printed material 74 of the mold 70 is a polymericmaterial, and more specifically, a polyurethane material. The printedmaterial 74 of the mold 70 may comprise any other suitable polymericmaterial in other embodiments (e.g., silicon, polycarbonate, etc.).Moreover, in some embodiments, the printed material 74 of the mold 70may comprise a metallic material or a ceramic material.

In embodiments where the mold 70 is made via SLS, a material of the mold70 may comprise a powdered material. For example, the material of themold 70 may comprise a metallic powdered material or a polymericpowdered material. Alternatively, in embodiments where the mold 70 ismade via SLA, the material of the mold 70 may comprise a polymericresin.

Making the mold 70 via the 3D printer 76 (i.e., via additivemanufacturing) may decrease a cost of making the mold 70 (e.g., byreducing the amount of time needed to manufacture the mold 70) andtherefore lead to a decrease in a production cost of the post-moldedexpandable component 12 _(x). Moreover, using the 3D printer 76 to makethe mold 70 may facilitate producing custom designs of the post-moldedexpandable component 12 _(x).

The mold 70 may be configured in any suitable way. For instance, anexample of configuration of the mold 70 is shown in FIG. 39. In thisexample, the mold 70 comprises first and second mold halves 71 ₁, 71 ₂which are complimentary to one another. For example, the first mold half71 ₁ may comprise a plurality of first connectors 73 ₁-73 _(C) (e.g.,protrusions, ridges, etc.) that are configured to fit a plurality ofsecond connectors 77 ₁-77 _(C) (e.g., recesses, holes, etc.) of thesecond mold half 71 ₂ to correctly position the first mold half 71 ₁relative to the second mold half 71 ₂ and to secure the two mold halves71 ₁, 71 ₂ together. The mold 70 may also comprise a sealing member 78(e.g., a gasket) to prevent or otherwise minimize loss of the materialto be molded in the mold 70 during molding. The mold cavity 72 of themold 70 is formed when the first and second mold halves 711, 712 aresecured to one another. In this example, the material of the mold 70comprises silicone. The material of the mold 70 may comprise any othersuitable material in other examples.

The mold 70 in which the expandable material 50 is molded may be made inany other suitable manner in other embodiments.

For instance, in some embodiments, the mold 70 may be thermoformed. Anexample of the mold 70 that is thermoformed is shown in FIGS. 40 and 41.In this example, each of the first and second mold halves 71 ₁, 71 ₂ ofthe mold 70 consists of a thermoformed sheet comprising a thermoformablematerial. That is, each of the first and second mold halves 71 ₁, 71 ₂is originally a sheet of thermoformable material that is heated andsubsequently deformed to acquire its final shape. As shown in FIGS. 42Aand 42B, a compression device 79 may be provided when molding theprecursor 12 _(x)* with the thermoformed mold 70 in order to compressthe sealing member 78 during molding (e.g., injection molding). Thecompression device 79 may comprise first and second members 81 ₁, 81 ₂being disposed on top and below the mold 70 such as to sandwich thefirst and second mold halves 71 ₁, 71 ₂ at a peripheral portion of thefirst and second mold halves 71 ₁, 71 ₂. An opening may be provided onone or both members 81 ₁, 81 ₂ of the compression device 79 to allow acertain amount of deformation of the mold 70 at a location of the moldcavity 72.

As the expandable material 50 molded into the precursor 12 _(x)* will besubsequently expanded, in this embodiment, the mold 70 may effectivelybe used to manufacture post-molded expandable components like thepost-molded expandable component 12 _(x) that have different sizes(i.e., by controlling expansion of the expandable material 50 after ithas been molded).

For example, in this embodiment, with additional reference to FIG. 22,the mold 70 is used to produce the precursor 12 _(x)* which may beexpanded into a post-molded expandable component of a first size 12_(x1) (e.g., a small size), a post-molded expandable component of asecond size 12 _(x2) (e.g., a medium size), or a post-molded expandablecomponent of a third size 12 _(x3) (e.g., a large size). The precursor12 _(x)* may be expanded into more sizes in other embodiments (e.g., ajunior size, an extra-large size). As such, a single mold 70 may allowmanufacturing post-molded expandable components 12 ₁-12 _(E) of varioussizes.

Upon having been molded into the precursor 12 _(x)* in the mold 70, theexpandable material 50 is subsequently subjected to a stimulus whichcauses it to expand into its expanded shape that is the scaled-upversion of the initial shape of the precursor 12 _(x)* and thatcorresponds to the three-dimensional configuration of the post-moldedexpandable component 12 _(x) constituting the pad 36 _(x) of the helmet10.

In this embodiment, there may be a substantial amount of time aftermolding of the expandable material 50 into the precursor 12 _(x)* in themold 70 and before expansion of the expandable material 50 into itsexpanded shape that is the scaled-up version of the initial shape of theprecursor 12 _(x)* and that corresponds to the three-dimensionalconfiguration of the pad 36 _(x), which will be referred to as asubstantial “post-molding pre-expansion amount of time”. The stimuluscausing expansion of the expandable material 50 may thus be initiatedafter the substantial post-molding pre-expansion amount of timefollowing molding of the precursor 12 _(x)* in the mold 70.

The substantial post-molding pre-expansion amount of time may allow theproperties of the expandable material 50 in its expanded shape to beenhanced, including its stiffness, resilience, and tensile strength, asdiscussed above. More particularly, during the substantial post-moldingpre-expansion amount of time, the expandable material 50 of theprecursor 12 _(x)* may undergo a chemical reaction (e.g.,polymerization) or other reaction that can enhance its properties, suchas its stiffness, resilience, and tensile strength, compared to if ithad been instantly or rapidly expanded upon being molded in the mold 70.

For example, in some embodiments, the substantial post-moldingpre-expansion amount of time for the expandable material 50 of theprecursor 12 _(x)* may be at least one hour, in some cases at least tenhours, in some cases at least one day, in some cases at least two days,in some cases at least three days, in some cases at least five days, insome cases at least seven days, and in some cases even more.

In this embodiment, expansion of the expandable material 50 of theprecursor 12 _(x)* into the three-dimensional configuration of the pad36 _(x) in response to the stimulus occurs outside of the mold 70 inwhich the precursor 12 _(x)*. That is, upon having been molded into theprecursor 12 _(x)* in the mold 70, the expandable material 50 is removedfrom the mold 70 and then subjected to the stimulus which causes it toexpand.

The stimulus causing expansion of the expandable material 50 is energytransmitted to the expandable material 50 causing its expansion. In thisembodiment, heat is the stimulus causing expansion of the expandablematerial 50. More particularly, in this embodiment, the expandablematerial 50 is subjected to heat generated by a heat source 80 whichcauses the expandable material 50 of the precursor 12 _(x)* to expandinto the post-molded expandable component 12 _(x). In this embodiment,as shown in FIG. 23, the heat source 80 comprises an oven 82 comprisinga thermally-insulated chamber and at least one heating element disposedwithin the thermally insulated chamber. In this example, the oven 82 ispowered electrically, however the oven 82 may be powered in any suitableway in other examples (e.g., a gas-powered oven). Moreover, the oven 82may be any suitable type of oven such as, for example, an industrialoven, a conventional oven, or a microwave oven. In other embodiments,the heat source 80 may be a hot liquid (e.g., the precursor 12 _(x)* maybe subject to a hot liquid bath) or a hot gas (e.g., hot air expulsed bya blower).

The oven 82 is configured to generate heat such as to attain andmaintain a given temperature within its insulated chamber. In thisexample, the given temperature is set by a user of the oven 82 (e.g.,via a control) to cause the precursor 12 _(x)* to be heated such thatthe expandable material 50 reaches its expansion temperature at whichthe expandable microspheres 60 ₁-60 _(M) of the expandable material 50expand. The expansion temperature of the expandable material 50, andthus of the precursor 12 _(x)*, may vary. For instance, in some cases,the expansion temperature of the precursor 12 _(x)* may be at least 70°C., in some cases at least 90° C., in some cases at least 110° C., insome cases at least 130° C., in some cases at least 150° C. and in somecases even more (e.g., 160° C.).

In order to cause the expandable material 50 of the precursor 12 _(x)*to expand to its expanded shape corresponding to the three-dimensionalconfiguration of the pad 36 _(x), the expansion temperature of theprecursor 12 _(x)* is held for a given amount of time. The given amountof time may be referred to as an “expansion time” of the precursor 12_(x)* since it is the time it takes for the expandable material 50 ofthe precursor 12 _(x)* to expand into the post-molded expandablecomponent 12 _(x). The expansion time of the precursor 12 _(x)* mayvary. For instance, in some cases, the expansion time of the precursormay be at least 10 seconds, in some cases at least 1 minute, in somecases at least 5 minutes, in some case at least 10 minutes, in somecases at least 20 minutes, in some cases at least 30 minutes, in somecases at least 40 minutes, and in some cases even more (e.g., 60minutes).

By controlling the expansion temperature, the expansion time and thequantity of the expandable microspheres 60 ₁-60 _(M) of the precursor 12_(x)*, an operator of the oven 82 is able to control the expansion ratioof the post-molded expandable component 12 _(x) and thus the size of thepost-molded expandable component 12 _(x) constituting the pad 36 _(x).In other words, by controlling the expansion temperature, the expansiontime and the quantity of the expandable microspheres 60 ₁-60 _(M) of theprecursor 12 _(x)*, the operator can produce the post-molded expandablecomponent 12 _(x) constituting the pad 36 _(x) in accordance to varioussizes (e.g., small, medium, large sizes).

Expansion of the expandable material 50 into the post-molded expandablecomponent 12 _(x) of the helmet 10 constituting the pad 36 _(x) may beperformed by any suitable entity.

In this embodiment, expansion of the expandable material 50 into thepost-molded expandable component 12 _(x) of the helmet 10 constitutingthe pad 36 _(x) may be performed by a manufacturer of the helmet 10during original manufacturing of the helmet 10. For instance, themanufacturer of the helmet 10 may use the molding apparatus 75 and themold 70 as described above to make the precursor 12 _(x)* and thereaftersubject the precursor 12 _(x)* to heat generated by the heat source 80(e.g., the oven 82) in order to cause the expandable material 50 of theprecursor 12 _(x)* to expand to form the post-molded expandablecomponent 12 _(x). As such, in this embodiment, the manufacturer of thehelmet 10 is able to make different sizes of the pad 36 _(x) fordifferent sizes of the helmet 10 by using the mold 70.

The post-molded expandable component 12 _(x) of the helmet 10constituting the pad 36 _(x) may be implemented in any other suitableway in other embodiments.

For instance, in some embodiments, as shown in FIG. 43, the expandablematerial 50 of the post-molded expandable component 12 _(x) may be oneof a plurality of expandable materials 150 ₁-150 _(E) of the post-moldedexpandable component 12 _(x) that have different properties from oneanother.

For example, in some cases, a given expandable material 150 ₁ of thepost-molded expandable component 12 _(x) may have a greater expansionratio than another expandable material 150 _(k) of the post-moldedexpandable component 12 _(x). As such the given expandable material 150₁ may expand more than the other expandable material 150 _(k) whensubjected to a similar stimulus.

In some examples, a given expandable material 150 ₁ of the post-moldedexpandable component 12 _(x) may have a different stiffness, hardness ordensity than another expandable material 150 _(k.) This may impartdifferent mechanical properties at different regions of the post-moldedexpandable component 150 _(k). For instance, an expandable material 150₁ that is more outwardly disposed than another expandable material 150_(k) (i.e., being more spaced apart from the player's head at a portionor an entirety of the post-molded expandable component 12 _(x)) may havea greater stiffness than the other expandable material 150 _(k). Forexample, the expandable material 150 ₁ that is more outwardly disposedthan the other expandable material 150 _(k) may have a greater stiffnessto protect the player's head from an impact while the other expandablematerial 150 _(k) that is more inwardly disposed may have a smallerstiffness so as to be more comfortable on the player's head.

The plurality of expandable materials 150 ₁-150 _(E) of the post-moldedexpandable component 12 _(x) may be formed via a multi-injection moldingprocess in which the plurality of expandable materials 150 ₁-150 _(E)are molded subsequently using a same molding apparatus. This may be doneby loading two or more different feeders of the molding apparatus withthe expandable materials 150 ₁-150 _(E) in order to inject theexpandable materials 150 ₁-150 _(E) into each mold cavity of a mold. Themold is movable within the molding apparatus (e.g., rotatable) to bringeach mold cavity into its “fill position” for each expandable material150 ₁. A similar multi-part casting process may be performed to form theplurality of expandable materials 150 ₁-150 _(E).

As another example, in some embodiments, as shown in FIG. 45, the pad 36_(x) may comprise a decorative outer layer 81 constituting at least partof an outer surface 88 of the pad 36 _(x). The decorative outer layer 81is colored differently than (i.e., includes one or more colors differentfrom that of) the expandable material 50 of the pad 36 _(x). In someexamples, the decorative outer layer 81 may include a graphicalrepresentation of: one or more alphanumeric characters that may formtext (e.g., a word, a message, etc.); one or more symbols (e.g., a logo,a sign, an emblem, etc.); one or more shapes or patterns; and/or one ormore real or imaginary objects (e.g., a person, an animal, a vehicle, animaginary or fictional character, or any other real or imaginary thing).

The decorative outer layer 81 may be implemented in any suitable way.For instance, in some embodiments, the decorative outer layer 81 maycomprise: a coating, such as a dye, paint (e.g., applied by spraying,dipping, etc.); a print (e.g., a direct printing, a pad printing,sublimation); a laser engraving; a sheet, such as a film; etc., or anycombination thereof.

In some embodiments, the decorative outer layer 81 may be part of thepad 36 _(x) before expansion of the expandable material 50 of the pad 36_(x), such that the decorative outer layer 81 expands with theexpandable material 50 when subjected to the stimulus (e.g., heat) aftermolding. For example, in some embodiments, the expandable material 50and the decorative outer layer 81 may be implemented by differentexpandable materials 150 ₁-150 _(E) as discussed above. In some cases,the decorative outer layer 81 may be applied onto an internal surface ofthe mold 70 so as to form the outer surface 88 of the precursor 12 _(x)*during molding.

In other embodiments, the decorative outer layer 81 may be providedafter expansion of the expandable material 50 of the pad 36 _(x). Forinstance, in some examples, the decorative outer layer 81 may be affixed(e.g., adhesively or chemically bonded) to the expandable material 50after the expandable material 50 has been expanded.

Alternatively or additionally, in some embodiments, the outer surface 88of the pad 36 _(x) may comprise a molded texture 89 imparted duringmolding of the precursor 12 _(x)*, i.e., during molding of theexpandable material 50 or an outer one of the expandable materials 150₁-150 _(E), where applicable. The molded texture 89 comprises apredetermined arrangement of relief elements 91 ₁-91 ₅ (i.e., one ormore recesses and/or one or more projections) of the outer surface 88 ofthe pad 36 _(x). The relief elements 91 ₁-91 ₅ are present in theprecursor 12 _(x)* as they are created by the mold 70 and then expandedduring expansion of the expandable material 50 or the outer one of theexpandable materials 150 ₁-150 _(E), where applicable.

As another example, in a variant, with additional reference to FIG. 24,the molding process of the precursor 12 _(x)* may be casting. Thecasting process of the precursor 12 _(x)* involves molding theexpandable material 50 in a mold 90 configured to produce the precursor12 _(x)*. More specifically, the casting process involves pouring theexpandable material 50, in a fluid state, into the mold 90 via a spruethereof in order to fill a mold cavity 92 of the mold 90 that has theshape of the precursor 12 _(x)*. Once the expandable material 50 hascured within the mold cavity 92, the precursor 12 _(x)* is formed andcan be removed from the mold 90. Additional finishing processes may becarried out on the precursor 12 _(x)* (e.g., deflashing).

While FIG. 24 illustrates the mold 90 configured in a certain way, themold 90 may be configured in any suitable way in other embodiments. Forinstance, the mold 90 may comprise additional features (e.g., a pouringcup, runners, gates, etc.).

In another variant, the molding process of the precursor 12 _(x)* may bethermoforming.

For instance, the expandable material 50 may be provided as athermoformable sheet 94 that is thermoformed in order to produce theprecursor 12 _(x)* from which the post-molded expandable component 12_(x) may be formed by expansion.

In this example, with additional reference to FIGS. 25A and 25B, anextrusion mechanism 96 (e.g., a sheet extruder) is used to produce thethermoformable sheet 94.

More specifically, the expandable material 50 is fed into the extrusionmechanism 96 (e.g., via a hopper) and circulated through a barrel of theextrusion mechanism 96. In some cases, the barrel may be heated tosoften or liquefy the expandable material 50 in order to facilitate itsdeformation as it is manipulated by the extrusion mechanism 96. Theexpandable material 50 is then fed into a die of the extrusion mechanism96 that forms the expandable material 50 into a sheet which issubsequently passed between a pair of rollers of the extrusion mechanism96 in order to reduce a thickness of the sheet. In some embodiments, asshown in FIG. 25B, the sheet thickness may instead be reduced by passingthe sheet through a scraper of the extrusion mechanism 96 (e.g.,supported on a conveyor mechanism). The extrusion mechanism 96 may alsocomprise a cutting subassembly (e.g., a slitter, a guillotine, etc.) forpartitioning the extruded sheet into multiple thermoformable sheets 94of a desired size. The extrusion process may be performed below theexpansion temperature of the expandable material 50.

The extrusion mechanism 96 may be configured in any other suitable way.For instance, the extrusion mechanism 96 may comprise additionalcomponents (e.g., a breaker plate) that are not shown. Moreover, thethermoformable sheet 94 may be formed in any other suitable way in otherexamples.

With additional reference to FIGS. 26 and 27, the thermoforming processof the precursor 12 _(x)* is performed using a molding apparatus 100. Inthis example, the molding apparatus 100 comprises a negative mold 102and a positive mold 104 that is shaped complementarily to the negativemold 102. As shown in FIG. 26, in order to begin the thermoformingprocess, the thermoformable sheet 94 is heated and placed on top of thenegative mold 102. As shown in FIG. 27, the positive mold 104 is thenpressed onto the negative mold 102 such as to sandwich thethermoformable sheet 94 between the positive mold 104 and the negativemold 102, thus causing the thermoformable sheet 94 to acquire the shapeof the negative and positive molds 102, 104. Once the thermoformablesheet 94 has cured, the positive mold 104 is disengaged from thenegative mold 102 and the formed precursor 12 _(x)* is removedtherefrom.

Additional finishing processes may be carried out on the precursor 12_(x)* (e.g., deflashing).

The molding apparatus 100 may be configured in any other suitable way.For instance, in some examples, the thermoforming process may be avacuum thermoforming process or any other suitable thermoformingprocess,

In a variant, in some embodiments, the stimulus for expanding theexpandable material 50 may be any other suitable stimulus (e.g.,microwave, ultraviolet (UV) light, etc.).

For instance, with additional reference to FIG. 44, in one example, theexpandable material 50 of the post-molded expandable component 12 _(x)may be caused to expand by infrared light. That is, subjecting theexpandable material 50 of the post-molded expandable component 12 _(x)to infrared light IR of a given intensity for a given exposure time maycause the post-molded expandable component 12 _(x) to expand. Thus bycontrolling the intensity and exposure time of the infrared light IR onthe post-molded expandable component 12 _(x), one may control theexpansion of the expandable material 50 of the post-molded expandablecomponent 12 _(x). As another example, the expandable material 50 of thepost-molded expandable component 12 _(x) may be caused to expand byultrasonic vibrations. For instance, subjecting the expandable material50 of the post-molded expandable component 12 _(x) to ultrasonicvibrations may cause molecules of the expandable material 50 to vibrateand thus generate heat. Thus, by controlling the intensity of theultrasonic vibrations and an amount of time to which the expandablematerial 50 is subjected to the ultrasonic vibrations, one may controlthe expansion of the expandable material 50 of the post-moldedexpandable component 12 _(x).

In a variant, in some embodiments, the expansion of the expandablematerial 50 into the post-molded expandable component 12 _(x) of thehelmet 10 constituting the pad 36 _(x) may be performed by a retailer orother entity selling the helmet 10 to buyers such as the user afteroriginal manufacturing of the helmet 10.

For instance, the expansion of the expandable material 50 into thepost-molded expandable component 12 _(x) may be done instore (i.e., atthe retailer's store/place of business) or otherwise at a location wherebuyers such as the player acquire helmets such as the helmet 10. To thatend, in such an example, the retailer may have an oven such as the oven82 described above installed instore in order to cause expansion of theexpandable material 50 at the retailer's store. More specifically, theretailer may be responsible for placing the precursor 12 _(x)* in theoven 82 in order to subject the precursor 12 _(x)* to heat at theexpansion temperature for a duration of the expansion time in accordancewith a size desired by the retailer. This may allow the retailer toproduce the post-molded expandable component 12 _(x) in sizes desired byhis/her customers on an individual basis.

Moreover, this may allow the retailer to provide custom-fit sizedpost-molded expandable components to buyers of the helmet 10. Forinstance, the precursor 12 _(x)* may be expanded by the retailer toconform to the player's head.

In another variant, in some embodiments, the expansion of the expandablematerial 50 into the post-molded expandable component 12 _(x) of thehelmet 10 constituting the pad 36 _(x) may be performed by the user ofthe helmet 10 after original manufacturing of the helmet 10.

For instance, the expansion of the expandable material 50 into thepost-molded expandable component 12 _(x) may be done at home or anotherlocation of the user's preference. To that end, in such an example, theuser may have an oven such as the oven 82 described above installed athis/her home in order to cause expansion of the precursor 12 _(x)*. Insuch a case, the oven 82 may be a standard kitchen oven. Morespecifically, the user may be responsible for placing the precursor 12_(x)* in the oven 82 in order to subject the precursor 12 _(x)* to heatat the expansion temperature for a duration of the expansion time inaccordance with a size desired by the user. This may allow the user toproduce the post-molded expandable component 12 _(x) in accordance tothe size he/she desires. That is, the user may form a custom-fittedpost-molded expandable component 12 _(x) that is ideal for his/her size.

In such a variant, the helmet 10 may come with an instruction guide thatinstructs the user on how to cause the precursor 12 _(x)* to expand intothe post-molded expandable component 12 _(x). For instance, theinstruction guide may include data establishing a relationship between adesired size of the post-molded expandable component 12 _(x) (e.g.,small, medium, large, etc.) and the expansion temperature and expansiontime of the precursor 12 _(x)*. The user may therefore use this data tocause the expandable material 50 of the precursor 12 _(x)* to expand toa size of the post-molded expandable component 12 _(x) that he/shedesires in accordance with his/her own body measurements. In some cases,the data provided in the instruction guide may correlate one or morehead dimensions (i.e., measurements of a head) to a given expansiontemperature and given expansion time of the precursor 12 _(x)* that arerecommended for expanding the expandable material 50 of the precursor 12_(x)* into a size of the post-molded expandable component 12 _(x) thatis appropriate for the given one or more head dimensions. For example,the data provided by the instruction guide may relate a given headwidth, head length and/or head height or any other head dimension withan expansion temperature and an expansion time of the precursor 12 _(x)*that is expected to yield a post-molded expandable component 12 _(x) ofa size suitable to accommodate a head having said given head width, headlength and/or head height or other head dimension.

While in this embodiment the inner liner 15 of the helmet 10 comprisesthe post-molded expandable components 12 ₁-12 _(E), in otherembodiments, another part of the helmet 10 may comprise one or morepost-molded expandable components such as the post-molded expandablecomponents 12 ₁-12 _(E). For instance, in some embodiments, as shown inFIG. 28, when the helmet 10 comprises a faceguard 14, a chin cup 82mounted to the chin strap 16 of the helmet 10 to engage a chin of theuser may comprise a post-molded expandable component 112 constructedusing principles described here in respect of the post-molded expandablecomponents 12 ₁-12 _(E). In some embodiments, at least part of the outershell 11 may comprise a post-molded expandable component that is similarto the post-molded expandable components 12 ₁-12 _(E). For instance, agiven one of the front shell member 22 and the rear shell member 24 ofthe outer shell 11 may comprise a post-molded expandable component.

Although in this embodiment the article of protective athletic gear 10is the helmet 10, in other embodiments, the article of protectiveathletic gear 10 may be any other article of protective athletic gearcomprising one or more post-molded expandable components constructedusing principles described herein in respect of the post-moldedexpandable components 12 ₁-12 _(E).

For example, in some embodiments, as shown in FIG. 29, the article ofprotective athletic gear 10 may be an arm guard (e.g., an elbow pad) forprotecting an arm (e.g., an elbow) of a user, in which the arm guard 10comprises a post-molded expandable component 212 constructed usingprinciples described herein in respect of the post-molded expandablecomponents 12 ₁-12 _(E) and constituting a pad 236 of the arm guard 10.

As another example, in some embodiments, as shown in FIG. 30, thearticle of protective athletic gear 10 may be shoulder pads forprotecting an upper torso (e.g., shoulders and a chest) of a user, inwhich the shoulder pads 10 comprise a post-molded expandable component312 constructed using principles described herein in respect of thepost-molded expandable components 12 ₁-12 _(E) and constituting a pad336 of the shoulder pads 10.

As another example, in some embodiments, as shown in FIG. 31, thearticle of protective athletic gear 10 may be a leg guard for protectinga leg of a user, in which the leg guard 10 comprises a post-moldedexpandable component 412 constructed using principles described hereinin respect of the post-molded expandable components 12 ₁-12 _(E) andconstituting a pad 436 of the leg guard 10.

In some cases, with additional reference to FIGS. 32 to 34, the articleof protective athletic gear 10 may be for a hockey goalie. For example,as shown in FIG. 32, the article of protective athletic gear 10 may be achest protector for a goalie for protecting the goalie's torso and arms.The chest protector 10 comprises a post-molded expandable component 712constructed using principles described herein in respect of thepost-molded expandable components 12 ₁-12 _(E). The post-moldedexpandable component 712 may constitute any portion of the chestprotector 10 (e.g., a chest portion, an upper arm portion, a lower armportion, an abdominal portion, etc.).

As another example, as shown in FIG. 33, the article of protectiveathletic gear 10 may be a blocker glove for a goalie for protecting thegoalie's hand and deflecting a puck or ball. In this example, theblocker glove 10 comprises a post-molded expandable component 812constructed using principles described herein in respect of thepost-molded expandable components 12 ₁-12 _(E). For example, thepost-molded expandable component 812 may constitute a board portion ofthe blocker glove 10 which the goalie uses to deflect pucks or balls.

As yet another example, as shown in FIG. 34, the article of protectiveathletic gear 10 may be a leg pad for a goalie for protecting a leg andknee of the goalie. In this example, the leg pad 10 comprises apost-molded expandable component 912 constructed using principlesdescribed herein in respect of the post-molded expandable components 12₁-12 _(E). For example, the post-molded expandable component 912 mayconstitute a padding portion of the leg pad 10 that is disposedunderneath an outer cover of the leg pad 10. In other examples, thepost-molded expandable component 912 may be an outermost layer of theleg pad 10 such that an object (e.g., a puck or ball) impact the leg pad10 impacts the post-molded expandable component 912 directly.

In some embodiments, the article of athletic gear 10 may be used forpurposes other than protection.

For example, in some embodiments, as shown in FIG. 35, the article ofathletic gear 10 may be a skate (e.g., an ice skate) for enabling a userto skate on a skating surface (e.g., ice), in which the skate 10comprises a post-molded expandable component 512 constructed usingprinciples described herein in respect of the post-molded expandablecomponents 12 ₁-12 _(E) and constituting at least part of a skate boot525 of the skate 10 (e.g., at least part of an outer shell or an innerliner of the skate boot 525 of the skate 10). As another possibility, insome embodiments, the skate 10 may comprise a post-molded expandablecomponent 519 constructed using principles described herein in respectof the post-molded expandable components 12 ₁-12 _(E) and constitutingat least part of a blade holder 547 of the skate 10 that holds a blade549 of the skate.

As another example, in some embodiments, with additional reference toFIGS. 36A to 38, the article of athletic gear 10 may be a sportsimplement for handling by a user, in which the sports implement 10comprises a post-molded expandable component 612 constructed usingprinciples described herein in respect of the post-molded expandablecomponents 12 ₁-12 _(E). In this embodiment, as shown in FIG. 36, thesports implement 10 is a stick and more particularly a hockey stick. Thehockey stick 10 comprises a shaft 620, a handle 622 disposed at aproximal end portion of the shaft 620, and a blade 624 disposed adjacenta distal end portion of the shaft 620. In this example, the blade 624 ofthe hockey stick 10 comprises the post-molded expandable component 612.For instance, in some embodiments, the post-molded expandable component612 may constitute at least part of a core 651 of the blade 624 that isdisposed internally of the blade 624 (i.e., between front and back walls653, 655 of the blade 624 that may be made of composite material such asfiber-reinforced polymeric material).

In a variant, another part of the hockey stick 10 may comprise thepost-molded expandable component 612. For instance, as shown in FIG. 37,in some examples, the handle 622 of the hockey stick 10 may comprise thepost-molded expandable component 612 or another post-molded expandablecomponent similar to the post-molded expandable component 612. Asanother example, in some cases, the blade 624 of the hockey stick 10 maycomprise the post-molded expandable component 612 while the handle 622of the hockey stick 10 may comprise another post-molded expandablecomponent 612.

As another example, with additional reference to FIG. 38, the sportsimplement 10 may be a lacrosse stick. The lacrosse stick 10 comprises ashaft 650, a handle 652 disposed at a proximal end portion of the shaft650, and a lacrosse head 654 disposed adjacent a distal end portion ofthe shaft 650. In this example, the handle 652 of the lacrosse stick 10comprises the post-molded expandable component 612. In other examples,other parts of the lacrosse stick 10 may comprise the post-moldedexpandable component 612 or another post-molded expandable component 612similar to the post-molded expandable component 612.

As another example, with additional reference to FIGS. 46A and 46B, thesports implement 10 may be a ball bat, such as a baseball bat or asoftball bat. The ball bat 10 comprises a handle 752, a barrel 754, anda tapered transition 755 between the handle 752 and the barrel 754. Inthis example, the barrel 754 comprises the post-molded expandablecomponent 612. For instance, in some embodiments, the post-moldedexpandable component 612 may constitute at least part of a core 751 ofthe barrel 754 that is disposed internally of the barrel 754 (i.e.,within a peripheral wall 757 of the barrel 754 that may be made ofmetallic material and/or composite material such as fiber-reinforcedpolymeric material). In other examples, other parts of the ball bat 10may comprise the post-molded expandable component 612 or anotherpost-molded expandable component 612 similar to the post-moldedexpandable component 612.

Although in embodiments considered above the article of athletic gear 10is hockey lacrosse, or baseball/softball gear, in other embodiments, thearticle of athletic gear 10 may be any other article of athletic gearusable by a player playing another type of contact sport (e.g., a“full-contact” sport) in which there are significant impact forces onthe player due to player-to-player and/or player-to-object contact orany other type of sports, including athletic activities other thancontact sports. For example, in other embodiments, the article ofathletic gear 10 may be an article of football gear for a footballplayer, an article of soccer gear for a soccer player, etc.

In other embodiments, a device comprising one or more post-moldedexpandable components constructed using principles described herein inrespect of the post-molded expandable components 12 ₁-12 _(E) may beanything other than an article of athletic gear and may thus be designedfor any suitable purpose. For example, this may include blunt traumapersonal protective equipment (PPE), insulating components, surf boards,swimming boards, automotive bumpers, motocross gear, cushioning devices,etc.

Certain additional elements that may be needed for operation of someembodiments have not been described or illustrated as they are assumedto be within the purview of those of ordinary skill in the art.Moreover, certain embodiments may be free of, may lack and/or mayfunction without any element that is not specifically disclosed herein.

Any feature of any embodiment discussed herein may be combined with anyfeature of any other embodiment discussed herein in some examples ofimplementation.

In case of any discrepancy, inconsistency, or other difference betweenterms used herein and terms used in any document incorporated byreference herein, meanings of the terms used herein are to prevail andbe used.

Although various embodiments and examples have been presented, this wasfor the purpose of describing, but not limiting, the invention. Variousmodifications and enhancements will become apparent to those of ordinaryskill in the art and are within the scope of the invention, which isdefined by the appended claims.

1.-228. (canceled)
 229. A method of making a helmet for protecting ahead of a user, the helmet comprising a shell comprising an outersurface of the helmet, the helmet comprising a liner disposed within theshell and comprising an inner surface of the helmet, the inner surfaceof the helmet being configured to contact the user's head, the linerincluding a pad, the method comprising: forming expandable material ofthe pad into an initial three-dimensional configuration; expanding theinitial three-dimensional configuration to an expanded three-dimensionalconfiguration that is a scaled-up version of the initialthree-dimensional configuration; and mounting the pad within the shell.230. The method of claim 229, wherein the forming comprises using 3Dprinting.
 231. The method of claim 230, wherein the using 3D printingcomprises using selective laser sintering (SLS).
 232. The method ofclaim 230, wherein the using 3D printing comprises usingstereolithography (SLA).
 233. The method of claim 230, wherein the using3D printing comprises 3D printing a mold and molding the expandablematerial of the pad in the mold.
 234. The method of claim 229, whereinthe expandable material comprises a polymeric substance and expandablemicrospheres.
 235. The method of claim 234, wherein the expandablemicrospheres constitute at least 20% of the expandable material byweight.
 236. The method of claim 234, wherein the expandablemicrospheres constitute at least 40% of the expandable material byweight.
 237. The method of claim 234, wherein the polymeric substance iselastomeric.
 238. The method of claim 234, wherein the polymericsubstance is polyurethane.
 239. The method of claim 229, wherein anexpansion ratio of the pad from the initial three-dimensionalconfiguration to the expanded three-dimensional configuration is atleast
 5. 240. The method of claim 229, wherein the expanding comprisesheating the expandable material.
 241. The method of claim 229,comprising providing an outer layer on the expandable material such thatthe outer layer constitutes at least part of an outer surface of the padand is colored differently than the expandable material.
 242. The methodof claim 229, wherein the pad comprises a plurality of regions thatdiffer in stiffness and are at least partly made of the expandablematerial.
 243. The method of claim 242, wherein: a first one of theregions of the pad is configured to be disposed closer to the user'shead than a second one of the regions of the pad; and the second one ofthe regions of the pad is stiffer than the first one of the regions ofthe pad.
 244. The method of claim 229, wherein the pad comprises aplurality of regions that differ in density and are at least partly madeof the expandable material.
 245. The method of claim 229, wherein: theexpandable material is a first expandable material; and the padcomprises a second expandable material different from the firstexpandable material.
 246. The method of claim 229, wherein theexpandable material is shaped into a plurality of parts of the pad thatare at least one of curved and angular and are present in the initialthree-dimensional configuration and in the expanded three-dimensionalconfiguration.
 247. The method of claim 229, wherein the pad comprises apredetermined arrangement of shaped elements that are made of theexpandable material, intersect one another, and are present in theinitial three-dimensional configuration and in the expandedthree-dimensional configuration.
 248. The method of claim 247, whereinthe shaped elements are regularly arranged.
 249. The method of claim247, wherein the shaped elements are relief elements of a texture of asurface of the pad.
 250. The method of claim 229, wherein the padcomprises empty spaces that are disposed between portions of theexpandable material and are present in the initial three-dimensionalconfiguration and in the expanded three-dimensional configuration. 251.The method of claim 242, wherein a first one of the regions of the padis configured to be disposed between the shell and a second one of theregions of the pad and is stiffer than the second one of the regions ofthe pad.
 252. The method of claim 229, wherein the expandedthree-dimensional configuration is thicker than the shell.
 253. Themethod of claim 229, wherein: the pad is a first pad; and the linerincludes a second pad distinct from the first pad.
 254. The method ofclaim 253, comprising: forming expandable material of the second padinto a second initial three-dimensional configuration; and expanding thesecond initial three-dimensional configuration to a second expandedthree-dimensional configuration that is a scaled-up version of thesecond initial three-dimensional configuration, wherein: the secondinitial three-dimensional configuration is different from the firstinitial three-dimensional configuration; and the second expandedthree-dimensional configuration is different from the second expandedthree-dimensional configuration.
 255. The method of claim 254, whereinthe expanded material of the second pad is different from the expandedmaterial of the first pad.
 256. The method of claim 254, wherein thesecond pad is movable relative to the first pad.
 257. The method ofclaim 256, wherein: the helmet comprises an adjustment mechanismconfigured to adjust a fit of the helmet on the user's head; and thesecond pad is movable relative to the first pad during operation of theadjustment mechanism.
 258. The method of claim 254, wherein a curvatureof an inner side of the first pad and a curvature of an inner side ofthe second pad form a continuity of one another.
 259. A method of makinga helmet for protecting a head of a user, the helmet comprising a shellcomprising an outer surface of the helmet, the helmet comprising a linerdisposed within the shell and comprising an inner surface of the helmet,the inner surface of the helmet being configured to contact the user'shead, the liner including a plurality of pads distinct from one another,the method comprising, for each pad: forming expandable material of thepad into an initial three-dimensional configuration; expanding theinitial three-dimensional configuration to an expanded three-dimensionalconfiguration that is a scaled-up version of the initialthree-dimensional configuration; and mounting the pad within the shell;wherein the initial three-dimensional configuration of a first one ofthe pads is different from the initial three-dimensional configurationof a second one of the pads such that the expanded three-dimensionalconfiguration of the first one of the pads is different from theexpanded three-dimensional configuration of the second one of the pads.260. A method of making an article of athletic gear wearable by a user,the article of athletic gear comprising a shell that is rigid andcomprises an outer surface of the article of athletic gear, the articleof athletic gear comprising a liner that is disposed within the shelland comprises an inner surface of the article of athletic gear, theinner surface of the article of athletic gear being configured tocontact the user, the liner including a pad, the method comprising:forming expandable material of the pad into an initial three-dimensionalconfiguration; expanding the initial three-dimensional configuration toan expanded three-dimensional configuration that is a scaled-up versionof the initial three-dimensional configuration; and mounting the padwithin the shell.
 261. The method of claim 260, wherein the formingcomprises using 3D printing.
 262. The method of claim 261, wherein theusing 3D printing comprises using selective laser sintering (SLS). 263.The method of claim 261, wherein the using 3D printing comprises usingstereolithography (SLA).
 264. The method of claim 261, wherein the using3D printing comprises 3D printing a mold and molding the expandablematerial of the pad in the mold.